model transforms

adapters.my-model\.js

import RESTAdapter from 'ember-data/adapters/rest';

export default class MyModelAdapter extends RESTAdapter {
  findRecord() {
    return {
      myModel: {
        id: 1,
        a: null,
        b: '2024-10-24T01:02:03',
        c: '2024-10-24T01:02:03',
        d: '2024-10-24T01:02:03',
        e: '2024-10-24T01:02:03'
      }
    };
  }  
}

classes.example\.js

export default class Example {
  constructor(value) {
    this._value = value; 
  }
  
  toString() {
    return `abc ${this._value} xyz` 
  }
}

models.my-model\.js

import Model from 'ember-data/model';
import attr from 'ember-data/attr';

export default class extends Model {
  @attr a;
  @attr b;
  @attr('string') c;
  @attr('date') d;
  @attr('example') e;
}

routes.application\.js

import Route from '@ember/routing/route';
import { inject } from '@ember/service';
import Example from '../classes/example';
const { log } = console;
 
export default class extends Route {
  @inject store;
  
  model() {
    return this.store.findRecord('my-model', 1);
  }
  
  setupController(controller, model) {
    log('a', model.a, model.a === null);
    log('b', model.b, typeof model.b === 'string'); 
    log('c', model.c, typeof model.c === 'string');
    log('d', model.d, model.d instanceof Date);
    log('e', model.e, model.e instanceof Example);
  }
}

serializers.my-model\.js

import RESTSerializer from 'ember-data/serializers/rest';

export default class MyModelSerializer extends RESTSerializer {}

templates.application\.hbs

a: {{@model.a}}<br />
b: {{@model.b}}<br />
c: {{@model.c}}<br />
d: {{@model.d}}<br /> 
e: {{@model.e}}<br />

transforms.example\.js

import Transform from '@ember-data/serializer/transform';
import Example from '../classes/example';

export default class extends Transform {
  deserialize(value) {
    return new Example(value);
  }

  serialize(exampleInstance) {
    return exampleInstance._value;
  }
}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0",
    "ember-data": "3.18.0"
  }
}